Femoral neck fracture implant

ABSTRACT

A device for implanting a bone fixation system comprises an insertion instrument extending from a proximal end to a distal end, the distal end having an engagement portion for removably engaging a proximal end of a bone plate, the insertion instrument having an elongated channel extending therethrough to permit insertion of a first protection sleeve therethrough, wherein a longitudinal axis of the elongated channel is coaxial with a longitudinal axis of a first opening extending through the bone plate and a first protection sleeve insertable into the elongated channel and guiding insertion of an anti-rotation screw therethrough and through the bone plate, a longitudinal axis of the first protection sleeve being angled with respect to the longitudinal axis of the elongated channel.

PRIORITY CLAIM

This application claims priority to U.S. Provisional Application Ser.No. 61/561,439 filed on Nov. 18, 2011 and entitled “Fastener” and U.S.Provisional Application Ser. No. 61/692,053 filed on Aug. 22, 2012 andentitled “Femoral Neck Fracture Implant,” the entire disclosures ofwhich are incorporated herein by reference.

FIELD OF THE INVENTION

The present invention generally relates to fasteners, fastenerassemblies, kits for fastener assemblies, methods of assembling fastenerassemblies, and methods of implanting fastener assemblies in a bone.

BACKGROUND

Femoral neck fractures are often treated with a pin or other implantinserted into the femoral head along an axis of the femoral neck. Onesuch product is the Stryker® Hansson® Pin System, which is a rod firstand second ends separated from one another by a side wall with nothreading on its outer surface. The Hansson® Pin has a hook deployablefrom a first end region for fixing the Hansson® Pin in the femoral head.The hook is deployed by pushing a shaft in the second end, which inturns deploys the hook through a hole in the side wall. Generally, twoor three ^(Hansson)® pins are inserted into the femoral head to fix thefemoral head and to facilitate healing of the femoral neck fracture.

Other known products for treatment of femoral neck fractures include theStryker® Gamma3® Hip Fracture system and the Smith+Nephew® Trigen®Intertan® Trochanteric Nail system. Both these systems include anintramedullary nail insertable into the femur and have rod-likefasteners insertable through the intramedullary nail into the femoralhead for stabilizing the femoral neck fracture. Additionally, each ofthese systems includes a feature for minimizing unwanted rotation of thefemoral head relative to the rod-like fastener, which is fixed in thenail. After the fastener is fixed, medial migration of the femoral headrelative to the neck fracture may cause an end of the rod-like fastenerto perforate the femoral head and damage the hip-joint. Another knownproduct is the Synthes® DHS® which includes a bone plate fixable to thefemur in the vicinity of the femoral head. The bone plate is preventedfrom rotating once positioned by a plurality of bone screws extendingthrough the plate into the femur. The bone plate includes a channelextending across a portion positioned to permit a rod-like fastener tobe passed through the channel into the femoral head to stabilize thefemoral head and allow healing of a femoral neck fracture. The rod-likefastener is impacted to drive it into the femoral head.

It is an object of the present invention to provide an improved systemfor femoral neck fracture fixation.

SUMMARY OF THE INVENTION

The present invention is directed to a device for implanting a bonefixation system comprising an insertion instrument extending from aproximal end to a distal end, the distal end having an engagementportion for removably engaging a proximal end of a bone plate, theinsertion instrument having an elongated channel extending therethroughto permit insertion of a first protection sleeve therethrough, wherein alongitudinal axis of the elongated channel is coaxial with alongitudinal axis of a first opening extending through the bone plateand a first protection sleeve insertable into the elongated channel andguiding insertion of an anti-rotation screw therethrough and through thebone plate, a longitudinal axis of the first protection sleeve beingangled with respect to the longitudinal axis of the elongated channel.

In a first aspect, the present invention provides an aiming instrumentto guide insertion of a bone fixation device into a bone, comprising anaiming arm including a first portion and a second portion, the firstportion extending from a proximal end to a distal end and having anelongated channel extending therethrough, the distal end having anengagement portion removably engaging a proximal end of the bonefixation device, a side wall of the aiming arm including an elongatedslot open to the elongated channel; and an elongated element removablyinsertable into the elongated channel, the elongated element having afirst shaft portion and a second shaft portion, the first shaft portionbeing inserted into the elongated channel and lockingly engaging theaiming arm, the second shaft portion extending through the elongatedslot and having an opening extending therethrough to guide insertion ofan anti-rotation screw therethrough and into the bone fixation device.

In a second aspect, the present invention includes a method ofimplanting a bone fixation device into a bone, comprising: engaging adistal end of a guide assembly to a proximal end of a bone fixationdevice so that a first portion of the guide assembly having an elongatedchannel extending therethrough is coaxial with a longitudinal axis ofthe bone fixation device, wherein the first portion extending from aproximal end to a distal end; inserting an elongated shaft portionthrough the elongated channel, the elongated shaft portion including afirst protection sleeve; inserting the bone fixation device into a shaftof the bone so that a first portion of the bone plate is positioned overan outer surface of the bone and a second portion of the bone plate isreceived within the bone; and inserting an anti-rotation screw throughthe first protection sleeve until a shaft of the anti-rotation screwextends out of the bone fixation device at an angle offset from thelongitudinal axis of the bone fixation device.

BRIEF DESCRIPTION OF THE DRAWINGS

Several embodiments of the invention will be described in the followingby way of example and with reference to the accompanying drawings inwhich:

FIG. 1 shows a first perspective view of a bone fastener assemblyaccording to a first exemplary embodiment of the invention;

FIG. 2 shows a second perspective view of the bone fastener assembly ofFIG. 1;

FIG. 3 shows a first perspective view of a bone plate of the bonefastener assembly of FIG. 1;

FIG. 4 shows a second perspective view of the bone plate of FIG. 3;

FIG. 5 shows a third perspective view of the bone plate of FIG. 3;

FIG. 6 shows a cross-sectional view of the bone plate of FIG. 3;

FIG. 7 shows a first perspective view of an implant shaft of the bonefastener assembly of FIG. 1;

FIG. 8 shows a second perspective view of the implant shaft of FIG. 7;

FIG. 9 shows a cross-sectional view of the implant shaft of FIG. 7;

FIG. 10 shows a partial cross-sectional view of the bone fastenerassembly of Fig.;

FIG. 11 shows a first surgical step for use of the bone fastenerassembly of FIG. 1;

FIG. 12 shows a second surgical step for use of the bone fastenerassembly of FIG. 1;

FIG. 13 shows a third surgical step for use of the bone fastenerassembly of FIG. 1;

FIG. 14 shows a fourth surgical step for use of the bone fastenerassembly of FIG. 1;

FIG. 15 shows a fifth surgical step for use of the bone fastenerassembly of FIG. 1;

FIG. 16 shows a sixth surgical step for use of the bone fastenerassembly of FIG. 1;

FIG. 17 shows a seventh surgical step for use of the bone fastenerassembly of FIG. 1;

FIG. 18 shows an eighth surgical step for use of the bone fastenerassembly of FIG. 1;

FIG. 19 shows a ninth surgical step for use of the bone fastenerassembly of FIG. 1;

FIG. 20 shows a tenth surgical step for use of the bone fastenerassembly of FIG. 1;

FIG. 21 shows a side view of the bone fastener assembly of FIG. 1 in afirst post-operative configuration;

FIG. 22 shows a cross-sectional view of the bone fastener assembly ofFIG. 21;

FIG. 23 shows a side view of the bone fastener assembly of FIG. 1 in asecond post-operative configuration;

FIG. 24 shows a cross-sectional view of the bone fastener assembly ofFIG. 23;

FIG. 25 shows a side view of a bone fastener assembly according to afirst alternate embodiment of the invention;

FIG. 26 shows a cross-sectional view of the bone fastener assembly ofFIG. 25;

FIG. 27 shows a side view of a bone fastener assembly according to asecond alternate embodiment of the invention;

FIG. 28 shows a cross-sectional view of the bone fastener assembly ofFIG. 27;

FIG. 29 shows a perspective view of a bone fastener assembly accordingto a third alternate embodiment of the invention;

FIG. 30 shows a perspective view of a bone fastener assembly accordingto a fourth alternate embodiment of the invention;

FIG. 31 shows a perspective view of a bone fastener assembly accordingto a fifth embodiment of the invention;

FIG. 32 shows a first surgical step for use of the bone fastenerassembly of FIG. 31;

FIG. 33 shows a second surgical step for use of the bone fastenerassembly of FIG. 31;

FIG. 34 shows a first embodiment of a kit for packaging any of the bonefastener assemblies according to the invention;

FIG. 35 shows a second embodiment of a kit for insertion devices for usewith the bone fastener according to the invention;

FIG. 36 shows a perspective view of a bone fastener assembly accordingto another embodiment of the invention;

FIG. 37 shows a first perspective view of a bone plate of the bonefastener assembly of FIG. 36;

FIG. 38 shows a second perspective view of the bone plate of FIG. 36;

FIG. 39 shows a cross-sectional view of the bone plate of FIG. 36;

FIG. 40 shows a first perspective view of an implant shaft of the bonefastener assembly of FIG. 36;

FIG. 41 shows a second perspective view of the implant shaft of FIG. 40;

FIG. 42 shows a third perspective view of the implant shaft of FIG. 40;

FIG. 43 shows a cross-sectional view of the implant shaft of FIG. 40;

FIG. 44 shows a side view of the implant shaft of FIG. 40;

FIG. 45 shows a perspective view of an anti-rotation screw of the bonefastener assembly of FIG. 37;

FIG. 46 shows a first surgical step for use of the bone fastenerassembly of FIG. 36;

FIG. 47 shows a second surgical step for use of the bone fastenerassembly of FIG. 36;

FIG. 48 shows a third surgical step for use of the bone fastenerassembly of FIG. 36;

FIG. 49 shows a fourth surgical step for use of the bone fastenerassembly of FIG. 36;

FIG. 50 shows a fifth surgical step for use of the bone fastenerassembly of FIG. 36;

FIG. 51 shows a perspective view of a bone fastener assembly accordingto another embodiment of the invention;

FIG. 52 shows a side view of the bone fastener assembly of FIG. 51;

FIG. 53 shows a perspective view of a bone fastener assembly accordingto another embodiment of the invention;

FIG. 54 shows a first perspective view of an implant shaft according toanother embodiment of the invention;

FIG. 55 shows a second perspective view of the implant shaft of FIG. 54;

FIG. 56 shows a cross-sectional view of the implant shaft of FIG. 54;

FIG. 57 shows a perspective view of an insertion device for the implantaccording to the invention in a first operative configuration;

FIG. 58 shows a perspective view of the device of FIG. 57 in a secondoperative configuration;

FIG. 59 shows a perspective view of the device of FIG. 57 in a thirdoperative configuration;

FIG. 60 shows a perspective view of the device of FIG. 57 in a fourthoperative configuration;

FIG. 61 shows a perspective view of the device of FIG. 57 in a fifthoperative configuration;

FIG. 62 shows a first perspective view of the device of FIG. 57 in asixth operative configuration; and

FIG. 63 shows a second perspective view of the device of FIG. 57 in thesixth operative configuration.

DETAILED DESCRIPTION

The present invention may be further understood with reference to thefollowing description and the appended drawings, wherein like elementsare referred to with the same reference numerals. The present inventionrelates to the treatment of fractures and, in particular, to devices forfixing femoral neck fractures. Exemplary embodiments of the presentinvention describe a bone plate having first portion positionableagainst an outer surface of a fractured or otherwise damaged bone and asecond portion partially inserted into the bone. A first bone screw holeextends through the first portion and a second bone screw hole extendsthrough the second portion. The second portion further receives a bonefixation shaft sized and dimensioned to extend across a fracturedportion of the femoral neck into the femoral head. The bone fixationshaft includes a transverse opening extending through a side wallthereof along a transverse opening axis angled with respect to a bonefixation shaft axis such that a bone fixation element (e.g., a bonescrew) inserted through the transverse opening extends away from theshaft into the bone to aid in fixation and compression of the fracturewhile also preventing rotation of the femoral head relative to the bone,as will be described in greater detail later on. It should be noted thatthe terms “proximal” and “distal” as used herein, refer to a directiontoward (proximal) and away from (distal) a user of the device. In anexemplary embodiment, the system and method disclosed herein may be usedfor femoral neck fractures. It is noted that although the exemplarysystem and method are directed to a fixation of a femoral head fracture,the exemplary bone fixation system may be used in any other bone in thebody without deviating from the scope of the invention.

The exemplary system and method according to the invention provide aminimally invasive surgical technique for treating femoral neckfractures using one or two incisions depending on soft-tissue thickness,as those skilled in the art will understand. Furthermore, since the boneplate and shaft implant of the invention are inserted into the bodysimultaneously, the exemplary system and method according to theinvention may be more quickly and accurately positioned as compared topresent systems. As will be described in greater detail below, theexemplary method according to the invention eliminates the need forimpacting the bone fixation device to insert it into the bone. It shouldalso be noted that the terms “medial” and “lateral” as used hereinindicate a direction toward (medial) and away from (lateral) a midlineof the body of a patient within which the bone fixation device is to beimplanted. Furthermore, the terms “cranial” and “caudal” as used hereinare intended to indicate a direction toward a head (cranial) and towardthe feet (caudal) of the patient within which the bone fixation deviceis to be implanted.

As shown in FIGS. 1-10, a bone fixation system 100 according to a firstembodiment of the present invention comprises a bone plate 102 sized andshaped for placement on a target portion of femoral shaft opposite thefemoral head (i.e., over a location through which an axis of the femoralneck passes). The bone plate 102 comprises a first portion 104 shaped toengage an outer surface of the target portion of the femur along a firstportion axis parallel to an axis of the shaft of the femur and a secondportion 106 extending away from the first portion along a second portionaxis 120 angled with respect to the first plane at an angle selected sothat, when the first portion 104 is positioned over the target portionof the femur, the second portion axis 120 extends along the axis of thefemoral neck. In one exemplary embodiment, the first and second portions104, 106 are angled such that a bone contacting surface 107 of the firstportion 104 encloses an angle a of approximately 130° relative to thesecond portion axis 120, as shown in FIG. 10. At this angle, the secondportion axis 120 encloses an angle β of approximately 40° relative to alocking hole axis 110 of a locking hole 108 extending through the plate102. It is noted, however, that any other angle may be used as requiredto accommodate a patient's anatomy without deviating from the scope ofthe invention. For example, the angle p may be 45°. The locking holeaxis 110 in this embodiment, extends substantially perpendicular to thefirst portion axis. However, those skilled in the art will understandthat the orientation of the locking hole axis 110 may be varied asdesired. The locking hole 108 includes a multi-faceted surface such asthreading 112 to threadedly engage a corresponding threading on a shaft12 of a bone fixation element 10 (e.g., a bone screw) insertedtherethrough. The bone fixation element 10 may be a standard lockingscrew known in the art. A proximal portion of the locking hole 108 mayinclude a non-threaded recess 114 to seat a head 14 of the bone fixationelement 10 as would be understood by those skilled in the art. An outersurface of the first portion 104 may be substantially rounded such thatthe first portion 104 has a smooth outer profile preventing soft tissueirritation.

The second portion 106 is substantially cylindrical and extends from thefirst portion 104 to a distal end 116 along a length selected so that,when the first portion 104 is positioned over the target portion of thefemur, the second portion 106 extends through the femoral neck to adesired position within the femoral head. A central elongated channel118 extends through the second portion along the second portion axis120. An outer surface of the channel is substantially smooth with theexception of an abutment 122 adjacent the distal end 116. The abutment122 extends proximally into the channel 118 a predetermined distance andincludes a proximal seat 124 and an elongated face 126. As will bedescribed in greater detail later on, the proximal seat 124 provides astop for an implant shaft 130 while the face 126 prevents and/orminimizes a rotation of the shaft 130 relative to the bone plate 102.

The bone fixation system 100 further comprises an implant shaft 130 forinsertion through the plate 102 along the axis of the femoral neck andthe second portion axis 120 into the femoral head. The shaft 130 isformed as a an elongated substantially cylindrical member extending froma proximal end 132 to a distal end 134 along a central longitudinal axis136. A diameter of the implant shaft in this embodiment is approximately10 mm. However, other dimensions may be used to accommodate differencein patient anatomy without deviating from the scope of the invention. Inan exemplary embodiment, the distal end 134 may be blunt to prevent theimplant shaft 130 from cutting through the bone 1. An outer surface ofthe implant shaft 130 comprises an elongated cutout 138 extending fromthe proximal end 132 to the distal end 134 and forming a flat surfaceconfigured to engage the face 126 of the abutment 122 preventingrotation of the shaft 130 relative to the plate 102. As those skilled inthe art will understand, a shape of the cutout 138 is selected so that,when implanted, forces tending to rotate the fractured femoral headrelative to the femoral shaft are countered, resulting in the femoralhead being kept in a desired stable alignment with the femoral shaft.That is, the cutout 138 eliminates the need for a friction fit betweenthe implant shaft 130 and the second portion 106 to prevent a rotationof the implant shaft 130. Any rotational force applied thereto isconverted to an angled moment arm applied to the implant shaft. Thecutout 138 is a portion of an outer surface of the implant shaft 130milled or otherwise formed to define a substantially planar face whichengages the face 126 in an operative configuration, as will be describedin greater detail later on. A proximal end of the cutout 138 comprises atab 140 extending radially therefrom by a distance selected to permitthe tab 140 to engage the seat 124 preventing the implant shaft 130 frombeing inserted distally past the seat 124 defining a maximum extent bywhich the shaft 130 may be inserted into the bone. In an operativeconfiguration, the implant shaft 130 engages the bone plate 102 via aform fit. As will be described in greater detail below with respect tothe method of use, the form fit engagement permits lateral and medialtelescoping migration of the implant shaft 130 relative to the boneplate 102 after implantation. This migration permits the implant shaft130 to move laterally as the head of the bone moves to a correctedposition during healing.

The implant shaft 130 comprises a first channel 142 extendinglongitudinally therethrough from the proximal end 132 to the distal end134 in alignment with the central longitudinal axis 136. In an exemplaryembodiment, the first channel 142 is dimensioned to receive a guide wire(e.g., a Kirschner wire) therethrough to guide insertion of the implantshaft 130 into the bone. The implant shaft 130 further comprises asubstantially cylindrical second channel 144 extending therethroughalong an axis 148 from the proximal end 132 to a distal opening 146 on aside wall of the implant shaft 130. The axis 148 in this embodiment isangled at approximately 7.5° relative to the central longitudinal axis136. In another embodiment, the angle may be 5° , 6°, 8° or any otherangle greater than 5°. In yet another embodiment, the angle may rangebetween 0° and 5°. As shown in FIG. 8, the distal opening 146 of thesecond channel 144 is circumferentially separated from the cutout. Dueto the angular orientation of the second channel 144 relative to theimplant shaft 130, an opening of the second channel 144 at the distalopening 146 is substantially oval to permit a shaft 22 of ananti-rotation screw 20 inserted therethrough to exit therefrom.Specifically, the second channel 144 has a substantially circularcross-section. However, due to the second channel 144 exiting theimplant shaft 130 at an oblique angle, as shown in FIGS. 7-9, the distalopening 146 has an oval shape. The proximal end of the second channel144 is formed with a threaded portion 150 to threadedly engage threadingformed on the shaft 22 of the anti-rotation screw 20. The threadedportion 150 may have a tapered diameter to engage a tapered diameter ofa head 24 of the anti-rotation screw 20 the diameter of the threadedportion 150 being selected to prevent the head 24 from being insertedtherepast.

FIGS. 11-20 depict an exemplary method of use of the bone fixationsystem 100. In a first step, a patient is placed in a supine position onan operating table and the fractured bone 30 is provisionally broughtinto a corrected alignment via one or more of traction, abduction andinternal rotation as would be understood by those skilled in the art. Astraight lateral incision approximately 3-4 cm in length is madeproximal to a tip of a greater trochanter. The iliotibial tract is thensplit lengthwise and the vastus lateralis muscle is detached dorsallyfrom the intramuscular membrane. The proximal femoral shaft of a bone 1is then exposed without retracting the periosteum. A guide wire isinserted through a center of the femoral head at a desired angle until adistal end of the guide wire extends into the subchondral bone, as thoseskilled in the art will understand. If desired one or more additionalguide wires may be inserted into the femoral head as would be understoodby those skilled in the art. A known reaming device (not shown) is thenguided over the guide wire to ream a bore hole for the insertion of animplant according to the invention. The reamer is then removed from thebone 30 and the physician measures the appropriate implant length andselects an appropriately sized implant shaft 130. The implant shaft 130is then inserted through the channel 118 of the second portion 106 ofthe bone plate 102 until engagement of the tab 140 with the seat 126prevents further distal movement of the implant shaft 130. The assembledbone plate 102 and implant shaft 130 are then attached to an insertioninstrument 40 including an arm portion 42 and an elongated shaft portion44, a distal end 46 of which removably grasps the bone plate 102, asshown in FIGS. 11-13. It is noted that although the arm portion 42 isdepicted with a curvature, any other shape may be used without deviatingfrom the scope of the invention. The arm portion 42 includes a firstopening 48 extending through a first portion at a first end thereof anda second opening 50 extending through a second portion at a second endthereof. As will be described in greater detail below, the first opening48 according to this embodiment, has a substantially circularcross-section to permit insertion of a substantially cylindrical firstprotection sleeve 60 therethrough. The second opening 50 has asubstantially oblong (e.g., oval, rectangular, etc.) cross-sectionalshape to permit insertion of a second protection sleeve 70 therethrough,as will also be described in greater detail below. In an exemplaryembodiment, the bone plate 102 is slidably inserted into engagement withthe distal end 46, although other attachment mechanisms may be employedwithout deviating from the scope of the invention. The exemplary system100 eliminates the need for an impactor to drive the bone plate 102 andimplant shaft 130 into the bone. In an alternate embodiment, however, animpactor (not shown) may be used to first impact the implant shaft 130into the femoral neck of a bone 1 and into the femoral head andsubsequently impact the bone plate 102 into a lateral portion of thebone 1 until the plate 102 seats flush against the bone. Specifically,once the bone plate 102 has been attached to the insertion instrument40, an impactor may be inserted through the bone plate 102 against theimplant shaft 130 to impact the system 100 into the bone. The impactor(not shown) and the guide wire (not shown) may then be removed from thebone, leaving the insertion instrument 40 and system 100 positioned inthe bone, as shown in FIG. 14.

A first protection sleeve 60 is then inserted through the first opening48 in the insertion instrument 40. The first protection sleeve 60 mayextend through the first opening 48 and into the distal end 46 of theinsertion instrument 40 at a predetermined angle relative to the angleof the elongated shaft portion 44. In an exemplary embodiment, the firstprotection sleeve 60 and elongated shaft 44 enclose an angle ofapproximately 40°, although other angles may be used without deviatingfrom the scope of the invention. The first protection sleeve 60 guidesthe drilling of a hole into the bone 1 to permit insertion of the bonefixation element 10 (i.e., a bicortical shaft screw) therein.Specifically, a drilling mechanism known in the art may be insertedthrough the first protection sleeve 60 to drill an opening through thelocking hole 108 of the bone plate 102 and into the bone 1. The drillingmechanism may then be removed and the bone fixation element 10 may beinserted through the first protection sleeve 60 and bone plate 102 andinto the bone 1. Dimensions of the bone fixation element 10 are selectedto permit bicortical insertion thereof through the bone 1, as thoseskilled in the art will understand. The first protection sleeve 60 maythen be removed from the insertion instrument, leaving the bone fixationelement 10 in place within the bone 1.

As shown in FIGS. 17-18, the second protection sleeve 70 may comprise afirst elongated shaft portion 72 having a first channel 74 extendingtherethrough, the first elongated shaft portion 72 being insertablethrough the insertion instrument. In an operative configuration, alongitudinal axis 75 of the first channel 74 is substantially alignedwith the longitudinal axis 136 of the implant shaft 130. The secondprotection sleeve 70 further comprises a second elongated shaft portion76 having a second channel 78 extending therethrough, a longitudinalaxis 77 of the second elongated shaft portion 76 being offset from thelongitudinal axis 75 by approximately 5° to align with the axis 148 ofthe implant shaft 130, as described in greater detail earlier anddepicted in FIG. 9. The elongated shaft 44 may comprise an elongatedslot (not shown) on a side wall thereof to permit insertion of secondprotection sleeve 70 to the position depicted in FIG. 18.

Once the second protection sleeve 70 has been seated against theproximal end 132 of the implant shaft 130, a drilling mechanism (notshown) may be inserted through the second channels 78 and 144 to preparethe bone 1 for the anti-rotation bone screw 20. As those skilled in theart will understand, in softer bone, pre-drilling may not be necessary.As would be understood by those skilled in the art, a driving mechanism(not shown) may then be used to insert the anti-rotation screw 20through the second protection sleeve 70 and implant shaft 130 and intothe bone 1. The second protection sleeve 70 and insertion instrument 40may then be removed from the body, leaving the system 100 implanted inthe bone 1. Once implanted, the head of the femur is prevented fromrotation relative to the bone 1 via the anti-rotation screw 20 and boneplate 102. The shaft 130 is permitted to migrate within a desired rangerelative to the bone plate 102. Specifically, the combined implant shaft130 and bone fixation element anti-rotation screw 20 insertedtherethrough are capable of migrating a distance x from theconfiguration of FIGS. 21-22 to the configuration of FIGS. 23-24. Thoseskilled in the art will understand that this migration of the implantshaft 130 relative to the bone plate 102 minimizes the risk of medialperforation of the implant shaft 130 through the femoral head afterimplantation and as the bone heals.

It is noted that although the exemplary method depicts the insertion ofthe bicortical screw 10 first, followed by the insertion of theanti-rotation screw 20, the order of insertion may be changed withoutdeviating from the scope of the invention to suit, for example, asurgeon's preference. For example, the method of insertion for thesystem 800 as described below is directed to the insertion of ananti-rotation screw first, followed by a bi-cortical screw.

FIGS. 25-26 depict a system 200 according to a first alternateembodiment according to the invention. The system 200 is formedsubstantially similarly to the system 100, wherein like elements havebeen referenced with like reference numerals. The system 200 comprises abone plate 102 and an implant shaft 230. The implant shaft 230 is formedsubstantially similarly to the implant shaft 130 with the exception of areduced diameter distal portion 240. The implant shaft 230 extends fromthe proximal end 132 to the distal end 234. The reduced diameter distalportion 240 extends proximally from the distal end 134 a predetermineddistance. As those skilled in the art will understand, the reduceddiameter portion 240 reduces the amount of bone removal needed forinsertion of the implant shaft 230 into the bone and has a wider spreadbetween the distal end 234 of the implant shaft 230 and distal end ofthe anti-rotation screw 20.

FIGS. 27-28 depict a system 300 according to a second alternateembodiment according to the invention. The system 300 is formedsubstantially similarly to the system 100, wherein like elements havebeen referenced with like reference numerals. The system 300 comprises abone plate 102 and an implant shaft 330 formed substantially similarlyto the implant shaft 130 with the exception of a threaded distal portion340. The implant shaft 330 extends from a proximal end 132 to a distalend 234 with the threaded distal portion 340 extending proximally fromthe distal end 134 a predetermined distance. As those skilled in the artwill understand, the threaded distal portion 340 aids in retention ofthe implant shaft 330 within the bone 1.

FIG. 29 depicts a system 400 according to a third alternate embodimentaccording to the invention. The system 400 is formed substantiallysimilarly to the system 100, wherein like elements have been referencedwith like reference numerals. The system 400 comprises a bone plate 102and an implant shaft 430. The implant shaft 430 is formed substantiallysimilarly to the implant shaft 130 with the exception of a position andangle of a channel 444 extending therethrough. Specifically, the channel144 of the system 100 extends from the proximal end 132 to a distalopening 146 positioned on a cranial surface of the implant shaft in anoperative configuration. In contrast, the channel 444 extends from theproximal end 132 to a distal end 446 positioned on a caudal surface ofthe implant shaft 430 in an operative configuration. A channel axis 448of the channel 444 is angled at approximately −5° relative to thecentral longitudinal axis 136. However, those skilled in the art willunderstand that this angle may vary as desired without departing fromthe scope of the invention.

FIG. 30 depicts a system 500 according to a fourth alternate embodimentaccording to the invention. The system 500 is formed substantiallysimilarly to the system 100, wherein like elements have been referencedwith like reference numerals. The system 500 comprises a bone plate 102and an implant shaft 530 formed substantially similarly to the implantshaft 130 with the exception of a position and angle of a channel 544extending therethrough. Specifically, the channel 544 extends from theproximal end 132 to a distal end 546 positioned on a surface of theimplant shaft 530 which, in an operative configuration, faces one of ananterior and a posterior direction. A physician may determine which ofthe systems 100, 400 and 500 to use in accordance with, for example, asize and location of a fracture in the bone, as those skilled in the artwill understand.

FIGS. 31-33 depict a system 600 according to a fifth alternateembodiment according to the invention. The system 600 is formedsubstantially similarly to the system 100, wherein like elements havebeen referenced with like reference numerals. The system 600 comprises abone plate 602 and the implant shaft 130, bone plate 602 being formedsubstantially similarly to the implant shaft 130 with the exception ofan additional locking hole extending therethrough. Specifically, thebone plate 602 comprises a central longitudinal channel 118. A firstlocking hole 608 is positioned caudally of the central longitudinalchannel 118 and is substantially similar to the locking hole 108. Asecond locking hole 609 extends through the bone plate 602 cranially ofthe central longitudinal channel 118. A hole axis 610 of the secondlocking hole is substantially parallel to the channel axis 120 of thecentral longitudinal channel 118 such that a bone fixation element 10′inserted therethrough does not intersect any other portion of the system600.

An exemplary insertion method for the system 600 is substantiallysimilar to the method disclosed earlier with respect to system 100.However, once the first and second bone fixation elements 10, 20 havebeen inserted, a third drill sleeve 80 is inserted through the insertioninstrument 40 to align with the second locking hole. A drillingmechanism (not shown) is inserted through the drill sleeve 80 and intothe bone to define the trajectory of the bone fixation element 10′. Adriving mechanism (not shown) is then inserted through the drill sleeve80 to screw the bone fixation element 10′ into the bone 1. The exemplarysystem 600 provides added structural support to the bone 1 and may beparticularly advantageous in bones with multiple fractures or otherwiseweaker bones.

As shown in FIG. 34, the systems 100, 200, 300, 400, 500 and 600 may bemanufactured and packaged as a kit 700 including the bone plate 102,602, implant shaft 130, 230, 330, 430, 530, and anti-rotation screw 20along with instructions for implantation as described above. The implantshaft 130, 230, 330, 430, 530 and anti-rotation screw 20 may be providedin corresponding dimensions to one another. The kit may be sold invarious implant shaft lengths to suit the requirements of a particularprocedure. The bone fixation element 10 may be offered separately. Thekit 700 may include a molded packaging 702 formed of plastic or anothersuitable material having a removable seal 704 provided thereover, theseal 704 maintaining the sterility of the system.

FIG. 35 depicts a single-use kit for the instruments required for thecompletion of a bone fixation procedure according to the invention, asdescribed above with respect to the exemplary method of use for thesystem 100. A kit 750 according to the invention may include theinsertion instrument 40, the corresponding removable shaft portion 44and the first and second protection sleeves 60, 70. In an operativeconfiguration, the removable shaft portion 44 is attached to anelongated shaft 46, which is further attached to the second protectionsleeve 70 via a Y-connector. A side wall of the insertion instrument 40includes a slot (not shown) permitting insertion of the Y-connectortherepast. The removable shaft portion 44 further comprises a tab 48including a protruding distal end 49 extending radially away therefrom.In an operative configuration, the tab 48 is received through the secondopening 50 with a snap-fit engagement. Specifically, the tab 48 isdeformed radially inward when being inserted through the second opening50. Once moved thereinto, the tab 48 moves radially outward to assumeits initial configuration so that the protruding distal end 49 isreceived within a corresponding portion of the second opening 50, thuslocking the shaft portion 44 to the instrument 40. The insertioninstrument 40 may be made of a low-cost plastic injection molding whilethe protection sleeves 60, 70 and shaft portion 44 may be formed of alow-cost metal injection molding. In another embodiment, the insertioninstrument 40 may be made of standard parts (e.g., standard tubing,etc.) connected to form the depicted structure. The kit 750 may be soldas a single unit for use with any of the exemplary systems 100, 200,300, 400, 500, 600, 800 disclosed herein.

FIGS. 36-50 depict a system 800 according to another alternateembodiment according to the invention. The system 800 is formedsubstantially similarly to the system 100, wherein like elements havebeen referenced with like reference numerals. The system 800 comprises abone plate 802 and an implant shaft 830. The implant shaft 830 is formedsubstantially similarly to the implant shaft 130 with the exception ofthe structural differences noted below.

The bone plate 802 comprises a first portion 804 shaped to engage anouter surface of the target portion of the femur along a first portionaxis parallel to an axis of the shaft of the femur and a second portion806 extending away from the first portion along a second portion axisangled with respect to the first plane at an angle selected so that,when the first portion is positioned over the target portion of thefemur, an axis of the second portion extends along the axis of thefemoral neck. The first portion 804 comprises a locking hole 808extending through the plate 802 along a locking hole axis 810 whichextends substantially perpendicular to a first portion axis. The lockinghole 808 is formed substantially similar to the locking hole 108 of thesystem 100 and may include a multi-faceted surface such as threading 812to threadedly engage a corresponding threading on the shaft 12 of thebone fixation element 10 (e.g., a bone screw) inserted therethrough. Anouter surface of the first portion 804 is substantially rounded suchthat the first portion 804 has a smooth outer profile substantiallymatching that of the target portion of the femur. The outer surface ofthe first portion 804 further comprises one or more recesses 805configured and dimensioned to permit grasping of the bone plate 802 bythe insertion instrument 40, as will be described in greater detail withrespect to the exemplary method below. The recess 805 may extendsubstantially parallel to an axis of the first portion 804. In anexemplary embodiment, first and second recesses 805 may be provided onopposing walls of the first portion 804 to permit grasping of the boneplate 802. Dimensions of each of the recesses may be selected to conformto the dimensions of a gripping portion of the implant holder

The second portion 806 is substantially cylindrical and extends from thefirst portion 804 to a distal end 816. A central elongated channel 818extends through the second portion along a second portion axis 820. Anouter surface of the channel 818 is substantially smooth with theexception of an abutment 822 adjacent the distal end 816. The abutment822 extends radially into the channel 818 a predetermined distance andis bordered on both sides by grooves 824. A cutout 826 extendsproximally from the distal end 816 of the second portion. In anexemplary embodiment, the cutout 826 is substantially rectangular withrounded corners and is open to the distal end 816. The cutout 826 ispositioned so that, in an operative configuration, the cutout faces acranial direction. Dimensions of the cutout 826 may be selected topermit the anti-rotation screw 80 to extend therefrom, as shown in FIGS.35 and 45-46. That is, the cutout 826 prevents the need for advancementof the implant shaft 830 out of the bone plate 102 beyond a thresholddistance. Rather, in smaller bones, the implant shaft 830 may extend outof the bone plate 802 by only a minimal required distance, with a distalend 846 of the second channel 844 be housed within the second portion806. In an operative configuration, the anti-rotation screw 80 may beinserted through the implant shaft 830 to extend out of the cutout 826.As those skilled in the art will understand, the cutout 826 may beformed with any length to permit use of the system 800 in bones havingvarying dimensions. Furthermore, for use in longer bones, the cutout 826may optionally be omitted. Furthermore, the cutout 826 allowstelescoping of the implant shaft 830 relative to the bone plate 802.

The second portion 806 further comprises first and second recesses 828provided on opposing walls adjacent a proximal end of the channel 818.The first and second recesses are configured and dimensioned to permitinsertion of a corresponding portion of a locking core therethrough toguide insertion of the bone plate 802 over the bone, as will bedescribed in greater detail below.

The implant shaft 830 is formed as a an elongated substantiallycylindrical member extending from a proximal end 832 to a substantiallyblunt distal end 834 along a central longitudinal axis 836. An outersurface of the implant shaft 830 comprises an elongated cutout 838extending from a proximal end 839 to the distal end 834, the cutout 838have a shape corresponding to the shape of the abutment 822 and grooves824 to permit engagement therewith. As described in greater detail withrespect to the system 100, this engagement prevents rotation of theshaft 830 relative to the plate 802. As those skilled in the art willunderstand, engagement of the abutment 822 with the proximal end 839 ofthe cutout 838 prevents the shaft 130 from extending distally out of theplate 802, defining a maximum extent by which the shaft 830 may beinserted into the bone. Furthermore, due to the hemispherical shape ofthe cutout 838, a rotational force applied to the implant shaft 830after implantation is converted to a substantially perpendicular momentarm, preventing wedging of the implant shaft 830 against walls of thesecond portion 806. The prevention of the wedging of the implant shaft830 also prevents high-friction forces that may influence the ability ofthe implant shaft 830 to telescope relative to the plate 802.

The implant shaft 830 comprises a first channel 842 extendinglongitudinally therethrough from the proximal end 832 to the distal end834 in alignment with a central longitudinal axis 836. The first channel842 is dimensioned to receive a guide wire (e.g., a Kirschner wire)therethrough to guide insertion of the implant shaft 830 into the bone.The implant shaft 830 further comprises a second channel 844 extendingtherethrough along an axis 848 from the proximal end 132 to a distalopening 846 on a side wall of the implant shaft 830, the distal opening846 being circumferentially separated from the cutout 838. The distalopening 846 is substantially oval to permit a shaft 82 of ananti-rotation screw 80 inserted therethrough to exit therefrom. Similarto the distal opening 146, the distal opening 846 is oval due to anoblique position of the substantially circular second channel 844relative to the implant shaft 830. The proximal end of the secondchannel 844 includes threading 850 to threadedly engage threading formedon the shaft 82 of the anti-rotation screw 80, as will be described ingreater detail below.

Whereas the threading 150 of the implant shaft 130 is substantiallytapered, the threading 850 is substantially cylindrical.

The anti-rotation screw 80 extends from a head 84 at a proximal end andalong the shaft 82 to a distal end 86. The shaft 82 includes a firstportion 88 having a first outer diameter selected to permit engagementwith the threading 850 of the implant shaft 830. Specifically, the firstportion 88 includes a first threaded region 89 including a double-leadthread to aid in engagement thereof with the threading 850. The firstportion 88 also includes a non-threaded tapered region 90 shaped toallow telescoping of the anti-rotation screw 80 when inserted into atarget orientation in the bone. The first portion 88 preferably has asubstantially tapered shape corresponding to a tapered shape of thesecond channel 844. A second non-threaded portion 92 extends distallyfrom the first portion 88. A diameter of the second portion 92 isgreater than a diameter of the tapered region 90, forming a telescopingstop 94 at a junction thereof. In an operative configuration, the secondportion 92 extends out of the implant shaft 830 and into the bone. Athird threaded portion 96 extends distally from the second non-threadedportion 94 and includes single lead spongiosa threading configured toengage bone in an operative configuration, as will be described ingreater detail with respect to the exemplary method below. As thoseskilled in the art will understand, the double-lead thread of the firstthreaded region 89 matches a pitch of the single-lead thread of thethird portion 96. In another embodiment, a higher pitch of the thread inthe third threaded portion 96 can be used to facilitate compression ofthe femoral head onto the shaft 82.

An exemplary method of use of the bone fixation system 800 issubstantially similar to the method of use of the system 100 describedin detail earlier with respect to FIGS. 11-20. Specifically, once thefractured bone 30 has been provisionally brought into a correctedalignment and an incision has been made, one or more guide wire areinserted into a center of the femoral head at a desired angle until adistal end of the guide wire extends into the subchondral bone, as thoseskilled in the art will understand. A known reaming device (not shown)is then guided over the guide wire to ream a bore hole for the insertionof an implant according to the invention. The implant shaft 830 is theninserted through the channel 818 of the second portion 806 of the boneplate 802 until engagement of the abutment 822 with the proximal end 839of the cutout 838 prevents further distal movement of the implant shaft830. The assembled bone plate 802 and implant shaft 830 are thenattached to the insertion instrument 40 including an arm portion 42 andan elongated shaft portion 44, a distal end 46 of which removably graspsthe recesses 805 of the bone plate 802. Once the bone plate 802 has beenattached to the insertion instrument 40, an impactor may be insertedthrough the bone plate 802 and implant shaft 830 to impact the system800 into the bone. The impactor (not shown) and the guide wire (notshown) may then be removed from the bone, leaving the insertioninstrument 40 and system 800 positioned in the bone.

As shown in FIGS. 48-49, the second protection sleeve 70 is theninserted through the second opening 50 and through the elongated shaft44 until a distal end thereof is seated against the implant shaft 830. Adrilling mechanism (not shown) may be inserted through the secondchannels 78 and 844 to prepare the bone 1 for the anti-rotation bonescrew 80. As those skilled in the art will understand, in softer bone,pre-drilling may not be necessary. As would be understood by thoseskilled in the art, a driving mechanism (not shown) may then be used toinsert the anti-rotation screw 80 through the second protection sleeve70 and implant shaft 830 and into the bone 1. The second protectionsleeve 70 and insertion instrument 40 may then be removed from the body,leaving the system 800 implanted in the bone 1. Once implanted, the headof the femur is prevented from rotation relative to the bone 1 via theanti-rotation screw 80 and bone plate 802.

As shown in FIG. 50, the first protection sleeve 60 is then insertedthrough the first opening 48 in the insertion instrument 40 to guide thedrilling of a hole into the bone 1 to permit insertion of the bonefixation element 10 (i.e., a bicortical shaft screw) therein.Specifically, a drilling mechanism known in the art may be insertedthrough the first protection sleeve 60 to drill an opening through thelocking hole 808 of the bone plate 802 and into the bone 1. The drillingmechanism may then be removed and the bone fixation element 10 may beinserted through the first protection sleeve 60 and bone plate 802 andinto the bone 1.

FIGS. 51-52 depict a system 900 according to yet another embodiment ofthe invention.

The system 900 is formed substantially similarly to the system 800 andincludes a bone plate 902 having first and second portions 904, 906 andan implant shaft 930 with one or more elastic deflecting structures at adistal end thereof. The implant shaft 930 includes an elongated channel942 extending therethrough from a proximal end (not shown) to a distalend 934. A second channel 944 extends therethrough at an angle relativeto a central longitudinal axis thereof to house the anti-rotation screw80, as described in greater detail with respect to earlier embodiments.The implant shaft 930 further comprises a plurality of elongated slots950 extending proximally from the distal end 934 and terminating at asubstantially circular cutout at proximal ends 952. In an exemplaryembodiment, the implant shaft 930 may include two slots 950 provided onopposing walls of the implant shaft 930 to define two compliant arms954. It is noted however, that any number of slots 950 may be providedwithout deviating from the scope of the invention. As those skilled inthe art will understand, the compliant arms 954 increase an overallelasticity of the implant shaft 930 by distributing a peak load appliedto the distal end 934, permitting the shaft 930 to deform instead offracturing when subjected to excessive loads. By allowing fordeformation of the implant shaft 930, the compliant arms 954 preventinadvertent penetration of the implant shaft 930 through the bone, asthose skilled in the art will understand.

FIG. 53 depicts a system 1000 according to another embodiment of theinvention. The system 1000 depicts an implant shaft 1030 formedsubstantially similar to the implant shafts 130, 830 described above.However, instead of being inserted through a bone plate, the implantshaft 1030 is insertable through an intramedullary nail 1002. Theintramedullary nail 1002 includes a transverse opening 1004 extendingtherethrough, the transverse opening 1004 having a shape formed by firstand second overlapping circular channels 1006, 1008. The first circularchannel 1006 is configured to permit insertion of the implant shaft 1030therethrough and extends through the intramedullary nail 1002 at a firstangle. The second circular channel 1008 is open to the first circularchannel and extends through the intramedullary nail 1002 at a secondangle different than the first angle. Specifically, an angle of thesecond circular channel 1008 substantially matches an angle of thesecond channel 144 relative to the first channel 142 of the implantshaft 1030. Thus, the anti-rotation screw 80 inserted through the secondchannel 144 is guided through the second channel 1008 and out of anopposing wall of the intramedullary nail 1002.

An outer wall of the implant shaft 1030 may include a cutout 1038configured to engage a respectively shaped abutment (not shown) providedin the first channel 1006. Engagement of the abutment (not shown) withthe cutout 1038 prevents rotation of the implant shaft 1030 relative tothe transverse opening 1004. Furthermore, engagement of the abutment(not shown) with a proximal end 1039 of the cutout 1038 limits a depthof insertion of the implant shaft 1030 into the bone, as described ingreater detail in earlier embodiments.

FIGS. 54-56 depict an implant shaft 1130 according to yet anotherembodiment according to the invention. The implant shaft 1130 is formedsubstantially similarly to the implant shafts 130, 830 except as notedhereinafter. The implant shaft 1130 may be used with any of the boneplates 102, 602, 802, 902 and intramedullary nails 1002 disclosed above.The implant shaft 1130 is formed as an elongated substantiallycylindrical member extending from a proximal end 1132 to a substantiallyblunt distal end 1134 along a central longitudinal axis 1136. An outersurface of the implant shaft 1130 comprises an elongated cutout 1138extending from a proximal end 1139 to the distal end 1134, the cutout1138 being formed substantially similar to the cutout 838. However,unlike earlier embodiments, the implant shaft 1130 does not comprise acentral longitudinal channel extending therethrough. Rather, the implantshaft 1130 comprises only a channel 1144 extending therethrough along anaxis 1148 from the proximal end 1132 to a distal opening 1146 on a sidewall of the implant shaft 1130 to receive, for example, an anti-rotationscrew (not shown) therethrough. Accordingly, unlike earlier embodiments,which may optionally be guided over a pre-positioned guide wire into thebone, the exemplary implant shaft 1130 may be inserted into the boneafter removal of the guide wire therefrom. That is, the implant shaft1130 may be guided into the bone via a hole pre-drilled therein.

Although the invention and its advantages have been described in detail,it should be understood that various changes, substitutions, andalterations can be made herein without departing from the spirit andscope of the invention as defined by the appended claims. For example,any of the implant shafts and bone plates disclosed herein mayoptionally be coated with Diamond-Like Carbon (DLC) to preventosseointegration thereof, as those skilled in the art will understandand/or to reduce friction and therefore improve telescoping between thebone plate and the implant shaft. Moreover, the scope of the presentapplication is not intended to be limited to the particular embodimentsof the process, machine, manufacture, composition of matter, means,methods and steps described in the specification. As one of ordinaryskill in the art will readily appreciate from the disclosure of thepresent invention, processes, machines, manufacture, composition ofmatter, means, methods, or steps, presently existing or later to bedeveloped that perform substantially the same function or achievesubstantially the same result as the corresponding embodiments describedherein may be utilized according to the present invention.

FIGS. 57-62 depict a kit 1200 according to another embodiment of theinvention as required for the completion of a bone fixation procedure.The kit 1200 is formed substantially similarly to the kit 750 describedearlier, with like elements being referenced with like referencenumerals. However, whereas the kit 750 is configured for single-use, thekit 1200 may be used any number of times to perform multiple procedure.It is noted that the kit 1200 may also be configured for single-usewithout deviating from the scope of the invention. Furthermore, whereasthe removable shaft portion 44 of the kit 750 engages the instrument 40with a click/snap-fit engagement, a removable shaft portion 1250 of thekit 1200 engages an instrument 1240 with a threaded engagement, as willbe described in greater detail hereinafter. It is noted, however, thatthe kit 1200 may also employ the snap-fit engagement of kit 750 withoutdeviating from the scope of the invention. The kit 1200 according to theinvention includes an insertion instrument 1240 extending from aproximal end 1242 including a curved arm 1244 to a distal end 1246. Afirst opening 1247 extends through the arm 1244 to guide the firstprotection sleeve 60 therethrough, as will be described in greaterdetail with respect to the exemplary method below. A second opening 1248extends into the proximal end 1242 permitting insertion of the removableshaft portion 1250 thereinto. The instrument 1240 also comprises anelongated slot 1249 on a side wall thereof to accommodate the width ofthe shaft portion 1250 when inserted therein.

The removable shaft portion 1250 includes a first elongated shaftportion 1252 extending from a first proximal end 1254 to a distal end1256 and including a first channel 1258 extending therethrough. In anoperative configuration, a longitudinal axis 1260 of the first channel1258 is substantially aligned with the longitudinal axis 136 of theimplant shaft 130. The removable shaft portion 1250 further comprises asecond elongated shaft portion 1262 formed substantially similarly tothe second protection sleeve 70 and extending from a second proximal end1264 to the distal end 1256. A second channel 1268 extends through thesecond shaft portion 1262 along a longitudinal axis 1270 offset from thelongitudinal axis 1260 by approximately 7.5° to align with the axis 148of the implant shaft 130, as described in greater detail with respect toearlier embodiments. The first and second elongated shaft portions 1252,1262 extend to a common distal end 1256 via a connecting element 1280.The connecting element 1280 according to this embodiment comprises anelongated slot 1282 extending through a side wall thereof to permitinsertion of the anti-rotation screw 20 therethrough and through theimplant 130 to extend into the bone, as will be described in greaterdetail with respect to the exemplary method below.

The first elongated shaft portion 1252 includes a locking element 1284at the first proximal end 1254. The locking element 1284 includes athreaded portion 1286 and a screw 1288 which may be rotated (e.g.,manually by a user) to screw the threaded portion 1286 into acorresponding threaded region (not shown) provided within the opening1248 of the instrument 1240. Specifically, rotation of the screw 1288rotates the entire first elongated shaft portion 1252 relative to theconnecting element 1280. In one embodiment of the invention, the firstelongated shaft portion 1252 is removably attached to the connectingelement 1280. In another embodiment, the first elongated shaft portion1252 is permanently attached to the connecting element 1280 and axiallymovable relative thereto within a predetermined range of motioncorresponding to an axial length of the threaded portion 1286 to permitscrewing and unscrewing thereof into the instrument 1240, as thoseskilled in the art will understand. The second elongated shaft portion1262 may also be either permanently or removably attached to theconnecting element 1280 as those skilled in the art will understand.

In accordance with an exemplary method according to the invention, apatient is placed in a supine position on an operating table and afractured femur is provisionally brought into a corrected alignment viaone or more of traction, abduction and internal rotation as would beunderstood by those skilled in the art. An incision is formed in theskin and the bone is reamed to create a bore hole for the insertion ofan implant according to the invention. The assembled bone plate 102 andimplant shaft 130 are then attached to the insertion instrument 1240 viaa sliding engagement between the distal end 1246 and a proximal end ofthe bone plate 102, as described in greater detail in earlierembodiments. The removable shaft portion 1250 is then inserted into theopening 1248 such that the distal end 1256 extends adjacent to thedistal end 1246 of the instrument 1240, as shown in FIG. 58. The screw1288 is then rotated to threadedly drive the first elongated shaftportion 1252 into the instrument 1240 and into threaded engagement witha threaded portion (not shown) of the opening 1248. The locking element1284 is configured so that, when the screw 1288 comes into contact withan outer surface of the instrument 1240, the first elongated shaftportion 1252 is locked against rotation or axial movement relative tothe instrument 1240.

Once the shaft portion 1250 has been locked to the instrument 1240, andthe bone fixation system 100 inserted into the bone, a drillingmechanism (not shown) may be inserted through the channel 1270 toprepare the bone for the anti-rotation bone screw 20. As those skilledin the art will understand, in softer bone, pre-drilling may not benecessary. A driving mechanism (not shown) may then be used to insertthe anti-rotation screw 20 through the second elongated shaft portion1262 and implant shaft 130 and into the bone, as shown in FIGS. 59 and60. In the implanted configuration, a distal end of the anti-rotationscrew 20 is separated from a distal end of the implant shaft 130 byapproximately 5 mm. As shown in FIGS. 61-63, the first protection sleeve60 is then inserted through the first opening 1247 in the insertioninstrument 1240. As described in greater detail in earlier embodiments,the first protection sleeve 60 extends through the first opening 1247and into the distal end 46 of the insertion instrument 40 at apredetermined angle relative to the angle of the first elongated shaftportion 1252 (e.g., 45°, etc.) until a distal end thereof is in contactwith the locking hole 108, as shown in the partial cutaway view of FIG.62. An optional drilling mechanism known in the art may be insertedthrough the first protection sleeve 60 to drill an opening through thelocking hole 108 of the bone plate 102 and into the bone. The drillingmechanism may then be removed and the bone fixation element 10 may beinserted through the first protection sleeve 60 and bone plate 102 andinto the bone 1. The first protection sleeve 60 and instrument 1240 maythen be removed, leaving the system 100 implanted in the bone. It isnoted that although the exemplary method depicts the insertion of theanti-rotation screw 20 followed by the bicortical screw 10 first, theorder of insertion may be changed without deviating from the scope ofthe invention to suit, for example, a surgeon's preference. Furthermore,although the kit 1200 is described with respect to the system 100, thekit 1200 may be employed with any of the systems 200, 300, 400, 500,600, 800 disclosed herein.

It will be appreciated by those skilled in the art that variousmodifications and alterations of the invention can be made withoutdeparting from the broad scope of the appended claims. Some of thesehave been discussed above and others will be apparent to those skilledin the art.

What is claimed is:
 1. A device for implanting a bone fixation system,comprising: an insertion instrument extending from a proximal end to adistal end, the distal end having an engagement portion for removablyengaging a proximal end of a bone plate, the insertion instrument havingan elongated channel extending therethrough to permit insertion of afirst protection sleeve therethrough, wherein a longitudinal axis of theelongated channel is coaxial with a longitudinal axis of a first openingextending through the bone plate; and a first protection sleeveinsertable into the elongated channel and guiding insertion of ananti-rotation screw therethrough and through the bone plate, alongitudinal axis of the first protection sleeve being angled withrespect to the longitudinal axis of the elongated channel.
 2. The deviceof claim 1, wherein the first protection sleeve and the elongatedchannel enclose an angle of one of 5°, 6°, 7.5° and 8°.
 3. The device ofclaim 1, wherein the first protection sleeve and the elongated channelenclose an angle greater than 5°.
 4. The device of claim 1, furthercomprising a second protection sleeve insertable into the insertioninstrument and guiding insertion of a locking screw therethrough andinto a second opening in the bone plate.
 5. The device of claim 4,wherein the second protection sleeve and the elongated channel enclosean angle of approximately 45°.
 6. The device of claim 4, wherein theinsertion instrument includes an arm extending away from the proximalend, the arm including an opening extending therethrough to guideinsertion of the second protection sleeve.
 7. The device of claim 1,further comprising an elongated shaft portion connected to the firstprotection sleeve, the elongated shaft portion being insertable into theelongated channel.
 8. The device of claim 7, wherein a proximal end ofthe elongated shaft portion includes a locking mechanism to lockinglyengage the insertion instrument.
 9. The device of claim 8, wherein thelocking mechanism includes a deflectable tab configured to engage acorresponding opening formed in the insertion instrument with asnap-fit.
 10. The device of claim 8, wherein the locking mechanismincludes a threaded portion and a screw mechanism, wherein rotation ofthe screw causes a rotation of the elongated shaft relative to the firstprotection sleeve to permit the threaded portion to threadedly engage acorresponding threaded opening in the insertion instrument.
 11. Thedevice of claim 7, wherein the elongated shaft portion is connected tothe first protection sleeve via a Y-connector.
 12. The device of claim1, wherein a side wall of the insertion instrument includes an elongatedslot open to the elongated channel, the slot permitting insertion of theY-connector therepast.
 13. The device of claim 1, wherein the device isa single-use assembly.
 14. The device of claim 1, wherein the device maybe used to perform a plurality of procedures.
 15. An aiming instrumentto guide insertion of a bone fixation device into a bone, comprising: anaiming arm including a first portion and a second portion, the firstportion extending from a proximal end to a distal end and having anelongated channel extending therethrough, the distal end having anengagement portion removably engaging a proximal end of the bonefixation device, a side wall of the aiming arm including an elongatedslot open to the elongated channel; and an elongated element removablyinsertable into the elongated channel, the elongated element having afirst shaft portion and a second shaft portion, the first shaft portionbeing inserted into the elongated channel and lockingly engaging theaiming arm, the second shaft portion extending through the elongatedslot and having an opening extending therethrough to guide insertion ofan anti-rotation screw therethrough and into the bone fixation device.16. The aiming instrument of claim 15, wherein the second portionincludes an opening extending therethrough, an opening axis of theopening being angled with respect to an axis of the elongated channel.17. The aiming instrument of claim 16, further comprising a protectionsleeve insertable through the opening toward the distal end of the firstportion such that a distal end of the protection sleeve is positionedadjacent to a proximal end of the bone fixation device.
 18. A method ofimplanting a bone fixation device into a bone, comprising: engaging adistal end of a guide assembly to a proximal end of a bone fixationdevice so that a first portion of the guide assembly having an elongatedchannel extending therethrough is coaxial with a longitudinal axis ofthe bone fixation device, wherein the first portion extending from aproximal end to a distal end; inserting an elongated shaft portionthrough the elongated channel, the elongated shaft portion including afirst protection sleeve; inserting the bone fixation device into a shaftof the bone so that a first portion of the bone plate is positioned overan outer surface of the bone and a second portion of the bone plate isreceived within the bone; and inserting an anti-rotation screw throughthe first protection sleeve until a shaft of the anti-rotation screwextends out of the bone fixation device at an angle offset from thelongitudinal axis of the bone fixation device.
 19. The method of claim18, wherein the implanted anti-rotation screw is offset from thelongitudinal axis of the bone fixation device by approximately 7.5°. 20.The method of claim 18, further comprising the step of inserting asecond protection sleeve through an opening formed in a second portionof the guide assembly and inserting a locking screw through the secondprotection sleeve and bone fixation device and into the bone.